I was shown achilles on my first lesson and practiced them for an hour with takedowns, was also shown heel hooks but was told they where dangerous and didn't practice them. I'm pretty sure the other white belts did though. In fact I have only seen one blue belt so far.

1. Un-post opponent's foot.
2. Grab their gi, and pull yourself towards them.
3. Try to kick your foot through so that they are putting pressure on your shin instead of your foot.
4. I'm pretty sure you can take a top position from here, take it and counter-attack.

I don't know any kneebar or heelhook defenses. The one time I escaped a kneebar was when I saw he was going for it, I grabbed the shin of that leg with my hand to keep it bent and jerked free. Other times, I just tap to kneebars when I can feel them start to lock in because I don't have the experience to judge when/how it's safe to escape and I don't want to mess up my knees.

That makes sense. I think I got shown it a little differently, I remember the instructor crossing his ankles and posting on the inside of the free leg. I may be wrong though. I was also told to roll onto my side for extra leverage.

First, you say that the ankle lock and heel hook are the only submissions you have been taught? Here is a friendly hint to speed up your overall success: LEARN TO PASS THE GUARD. If you are a one trick pony who can't pass, and always goes for the ankle lock than you are going to suck. Forget going for the submission from everywhere all the time, learn control and positioning first.

Second, if you ARE going to go for a footlock from inside the guard there are a couple of details to remember. Don't go for one unless you have secured his foot AND he does not have ahold of your head/gi/wrist. If he does have ahold of one of those, break that grip before you drop back because he will just ride up on you. Remember : positioning first. If you don't have a good shot at getting something without getting countered, forget it. Put it in terms of MMA - you go for a footlock to finish the fight and he comes up on you. Now he is on top, possibly mounting you and you are going to get punished. Badly. Better you had stayed in his guard for some GnP to open up a better position for that footlock instead of just 'going for it'.

Third, one of the most often overlooked aspects of dropping back for the footlock is LAT MUSCLE control. Meaning, squeeze the **** out of his leg by pressing your elbow into your side BEFORE you apply the leg lock. This will help in a lot of ways. If you have any doubts about how this affects a footlock, try putting a footlock on your bud without squeezing your lat muscle. Then do it while squeezing. Huge difference. And that movement can and should be executed as you drop back and before you begin to arch and crank.

BTW - I am not going into the details of where your feet should be. There are a few good methods, one invincible method, but overall everyone has their own preference and it will change as people squirm around. I'll let others touch on how to control with your legs.

To summarize: Learn to pass, don't go for it if they have a grip on you, and use your lat muscle when you drop back.

As far as I know I haven't been shown passing the guard yet, did a whole lesson on escaping from the mount. I'm guessing passing the guard is escaping somebodys guard while putting them in yours...

I didn't even think about squeezing my elbow against my side, that sounds like good advice.

The reason I'm interested in getting better at this one submission is, the advice given to me by fellow students "It's better to get tapped 20 times while working to better one submission than trying out lot's of new submissions". This is the only one I've been shown properly and it's the closest I've got to tapping out anybody with more experience.